For many years, motor vehicles have been equipped with airbags and airbag systems. These airbag systems are designed to inflate one or more airbags in the event of an accident or crash. These inflated airbags become positioned on the interior of the vehicle such that the occupant impacts the airbag rather than the steering wheel, the dashboard, or other portions of the vehicle interior.
In order to protect a vehicle driver from frontal impact, an airbag is often positioned as part of the vehicle's steering wheel. These systems are referred to as “steering wheel” airbag systems or “driver” airbag systems. The steering wheel airbag system will generally position the airbag at or near the center or hub of the steering wheel. Steering wheel spokes generally will connect the steering wheel hub to the outer rim of the steering wheel. Steering wheel airbag systems are designed such that when deployed, the airbag will generally cover all portions of the steering wheel, including the hub, the spokes, and the outer rim. When the steering wheel is covered by the inflated airbag, the driver will be prevented from harmfully impacting the steering wheel.
Steering wheel airbag systems generally comprise an airbag cover and a housing that houses the uninflated airbag. The cover, the housing, and the enclosed uninflated airbag are generally referred to as the “airbag module.” The airbag cover is generally attached directly to the housing. The airbag module is attached to the steering wheel via attachment features. These attachment features can be part of the housing or a separate component attached to the housing. The cover includes a tear seam and is positioned between the airbag and the vehicle seat. During an accident or crash, the cover will tear along the tear seam to allow the inflated airbag to become positioned in the vehicle interior.
FIG. 1 is a representation of the prior art representation of a steering wheel assembly 10. Specifically, the steering wheel assembly 10 includes an airbag 12, an airbag cover 14, and an inflator 22. The airbag 12 and the cover 14 are attached to an airbag housing 18, which is generally a metal plate or ring. The airbag 12 and housing 18 may also be attached to an inflator 22. The housing 18 is secured to an attach plate 19 which is then secured to the steering wheel armature 20.
One of the challenges in designing these steering wheel airbag modules is to position the airbag module as part of the steering wheel, yet still create a visually appealing steering wheel system. For example, when a steering wheel airbag module is positioned proximate the center or hub of the wheel, a gap or opening may be formed between the edge of the airbag module and the steering wheel spoke. Consumers generally do not prefer to see large gaps between the airbag module and other portions of the steering wheel system. For this reason, vehicle manufactures consistently seek new designs for steering wheel airbag systems that can control or eliminate the gap between the spokes and the airbag module.
One method that has been designed to reduce the gap between the airbag module and the steering wheel spoke is to construct the airbag cover with overlaps that cover/hide the gap. Unfortunately, this method slightly raises the overall costs of producing the airbag cover in that it requires that the cover include additional material. However, if the cover overlaps to cover the gap, the resulting structure may not be very cosmetically appealing to consumers.
Some manufacturers have even attempted to integrally mold the steering wheel hub to the cover, thereby providing a seamless interface between the airbag module and the steering wheel spokes. This method can eliminate all issues regarding the gap. At the same time, this method is very expensive and may require the use of a more expensive material for making the cover. (However, this method may be used when the manufacturer wanted a perfect gap—i.e., no gap). This integrally molded system may further require expensive methods for attaching the airbag module to the steering wheel. The increased costs associated with the integrally molded steering wheel systems means that such systems are generally disfavored.
More recently, vehicle manufacturers have desired less expensive means for controlling the size of the gap between the steering wheel spokes and the airbag module. Some of these recent designs are referred to as having a “floating” airbag cover because the airbag cover is loosely and moveably attached to the housing These floating covers provide adequate control of the gap between the airbag module and the spokes. At the same time, the floating covers can be expensive to manufacture and may require special, expensive hardware to properly connect and/or position the cover. These types of specially-designed components add to the cost, weight and complexity of the airbag module.
Based upon the foregoing, it is clear that a need exists for a new type of steering wheel airbag module that adequately controls the gap between the spokes and airbag module, but is easy to install and inexpensive to manufacture. Such a device is disclosed herein.